Real-time, functional queues, in Fungi

[matthewhammer]

Implement the following Elm library/data structure, in Fungi:

http://matthewhammer.org/courses/pfp-s18/lectures/RealTimeQueues/index.html

Steps:

• Writing out (by hand) the type and effect indices for the rotate helper function
• Do the same for the other operations in the library
• Try to write and type-check with this implementation of Fungi in Rust

See also:

• Okasaki, Chapter 7.1—7.2.
• Real-time queues in Haskell